The present invention relates to an air circulating fan and more particularly to a fan for circulating an air stream in an air treating environment.
The heating and cooling art has employed numerous fan arrangements for moving and circulating treated air to preselected locations, often utilizing both primary and auxiliary fan arrangements as specific environmental conditions dictate. Consideration has been given to, but not limited to, such factors as air movement efficiency and the cost thereof, the amount of cubic feet of air to be moved to a given location in a given time period, the sound levels produced by the air moving equipment, the amount of air waste in delivering the desired quantity of air to such given location, and the general complexity and maintenance of the air circulating fan structure involved. Several types of fan structures, particularly in booster fan arrangements have addressed one or more of the aforementioned factors, attention being directed to U.S. Pat. No. 4,722,266, issued to D. D. Deckerton, Feb. 2, 1988, which discloses an auxiliary air-flow boosting device which includes an induction motor, power controlled, driven fan disposed in a specific flow-through housing adapted to be sealed to a primary air source; U.S. Pat. No. 4,754,697, issued to C. K. J. Asselbergs on Jul. 5, 1988, which discloses a housing mounted tangential flow impeller with extendable housing legs; U.S. Pat. No. 4,846,399, issued to C. K. J. Asselbergs on Jul. 11, 1989, which discloses a somewhat similar flow-through boosting device and which concentrates on the fan blade shape at the impeller tips to expel air therefrom in a largely radial direction at 35.degree. to the impeller plane; U.S. Pat. No. 4,809,593, issued to C. K. J. Asselbergs on Mar. 7, 1989, which discloses a flow-through booster device which concentrates on the sealing arrangement with the primary air source; U.S. Pat. No. 5,054,380, issued to E. S. Hubbard on Oct. 8, 1991, which discloses a flow-through housing with radial flow impellers; U.S. Pat. No. 5,489,238, issued to C. K. J. Asselbergs on Feb. 6, 1996, which discloses still another flow-through housing with a centrifugal fan rotor; U.S. Pat. No. 5,632,677, issued to L. V. Elkins on May 27, 1997, which discloses a plurality of venting fans mounted in an outlet register; and, finally to U.S. Pat. No. 5,829,956, issued to Y. Chen et al. on Nov. 3, 1998, which discloses a fan blade assembly with fan blades having different curvatures from the inventive fan blade structure described herein.
None of these above-mentioned fan arrangements however, teaches the unique and novel air circulating fan structure as described herein, the inventive fan structure being capable of being utilized with both primary and booster arrangements in a straightforward, efficient, and economical manner with a minimum of maintenance and with the capability of efficiently delivering a maximum amount of air being moved through a preselected outlet with a minimum of noise and with a minimum of air waste.
Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth herein.